乙基 7-羟基庚-2-烯酸乙酯

反应条件: temp:0.01; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: To a solution of 7-hydroxy-hept-2-enoic acid ethyl ester (99.9 g, 0.58 mol) in tetrahydrofuran prepared in the previous step, cooled with ice-water bath, was added sodium hydride (4.80 g, 0.12 mol, 60%) in two portions. The mixture was stirred at 0° C. for 2 h and then at room temperature for 2 h. The mixture was neutralized with a 1 M aqueous hydrochloric acid solution (pH ˜5.0-6.0). Water (1 L) was then added and the mixture was extracted with ethyl acetate (3×1 L). The combined organic layers were dried over anhydrous sodium sulfate and concentrated in vacuo. The residue was treated with hexanes/ethyl acetate (3×800 mL, hexanes/ethyl acetate=10/1, v/v). The mixture was filtered and dried over anhydrous sodium sulfate. The filtrate was concentrated and the crude product was purified by flash column chromatography (QingDao silica gel, 200-300 mesh, 10% ethyl acetate/hexanes) to afford (tetrahydro-pyran-2-yl)-acetic acid ethyl ester (77.1 g, 77% yield). cooled with ice-water bath at room temperature for 2 h the mixture was extracted with ethyl acetate (3×1 L) The combined organic layers were dried over anhydrous sodium sulfate concentrated in vacuo The residue was treated with hexanes/ethyl acetate (3×800 mL, hexanes/ethyl acetate=10/1 The mixture was filtered dried over anhydrous sodium sulfate The filtrate was concentrated the crude product was purified by flash column chromatography (QingDao silica gel, 200-300 mesh, 10% ethyl acetate/hexanes)

反应条件: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

实验步骤: A solution of 2-hydroxytetrahydropyran (59.2 g, 0.58 mol) and triphenyl-λ5-phosphanylidene)-acetic acid ethyl ester (201.3 g, 0.58 mol) in tetrahydrofuran (1.2 L) was heated at reflux for 14 h. The mixture was cooled to room temperature to afford 7-hydroxy-hept-2-enoic acid ethyl ester in tetrahydrofuran and was then used directly in the next step. at reflux for 14 h